Improvement in hoisting-machines



UNITED STATES PATENT QFFICE.

HENRY J. REEDY, OF CINCINNATI, OHIO.

IMPROVEMENT IN HOlSTlNG-MACHINES.

To all whom it may concern:

Be it known that I, HENRY J. REEDY, of the city of Cincinnati, in thecounty of Hamilton and State of Ohio, have invented certain new anduseful Improvements in Hoisting-lilachines, of which the following is aspecifica tion:

The object of my invention is a cheap, durable, and simple device for ahoisting-machine, whereby, in the event of an unexpected stoppage of theplatform in its descent, the hoisting-cylinder will cease to revolve,thereby preventing the unwinding, entanglement, and

breakage of the hoisting-cord or the hoisting apparatus. The nature ofmy device consists in deepening one of the journals of thehoisting-axle, and in arranging a ratchet-wheel or arm on saidhoisting-axle and a stationary pawl on the frame of said journal in sucha manner that when the strain upon the hoisting-cord is relieved saidhoisting-axle falls to the bottom of the oblong journal, and the saidratchetwheel engages said pawl and stops the revolution of thehoisting-axle at the same time that, by means of a clutch, the operativemachinery disengages itself from the hoistingaxle and continues torevolve without injury, and so that, when said hoisting-axle is liftedto the top of said oblong journal, said ratchet wheel is disengaged fromthe said stationary pawl, and, the hoisting-axle being forced by aspring to engage with the operative machinery, the machine is againready for operation.

In the accompanying drawing, Figure 1 is a side elevation of ahoisting-machine embodying my improvement, showing the relative positionof the various parts of the machinery when the platform descends withoutstoppage, the side of the slotted journal being broken away to show thedepth of said journal. Fig. 2 is a side elevation of the same machinewith the platform removed, showing the relative position of the variousparts of the machinery when the platform refuses to descend. Fig. 3 isan elevation of that end of the hoisting apparatus which is at the lefthand in Fig. 2, showing the pulleys and gearing for turning thehoisting-axle. ratchet-wheel which engages the arm.

General Description. A A are uprights, by which the platform is Fig. 4is a view of the guided in its ascent and descent. K is a crosspiece atthe top of the platform supporting the journal H, in which is a pulley,E, and the journal H, in which is pulley E. B is the sliding platform. GO are the uprights of the same. By a suitable device. 0 slides upon theguides A and 0 upon A. B is the crosspiece at the top of the uprights OG, which connect them together. D is the hoisting-cord, made of anysuitable material. One end of D is fastened to the cross-piece B. From Bthis cord passes up over pulley E and over pulley E, then down andaround the hoisting-drum M. X is the axle of the hoisting-drum,journaled at Y in hanger W and at S in hanger W. This journal S is of aslotted shape, and about three times as long as the diameter of the axleX, or so long that when the axle X falls to the bottom of the journalthe teeth of the ratchet-wheel will engage the stationary pawl Z. Thisstationary pawl is fastened to hanger'WV, usually under theratchet-wheel, and on the opposite side of said hanger from that onwhich the hoisting-drum is. Y is a ratchet wheel with any desired numberof teeth, and fastened to and turned by said hoisting-axle. As amodification of the said ratchet-wheel an arm may be used, if preferred,attached to the axle, and engaging or disengaging the pawl as thehoisting-axle is raised or lowered in the slot. M is the hoisting-drumbetween the hangersW and W. It is fastened to axle X, which operates it.Upon that end'of the axle X which passes through and extends beyondhanger G is fastened onehalf of a clutch, N, said half of the clutchbeing contiguous to its other complementaryhalf, N, hereinafter alludedto. An elliptical spring, 1 is-placed between the hanger W and theadjacent end of the drum M. This spring has,

at its middle, a collar, through which the axle X passes. and holds itin place. This collar presses against the hanger \V, while the points ofIsa-id spring press against the end of the drum.

I do not, however, deem this particular form of spring essential to myinvention, but claim the right to introduce any kind of spring at anypoint in the apparatus as will serve eifect- For instance, a spiively topress clutch N. ral spring might be introduced in place or spring F, ora short spring of a desirable form might be placed outside of hanger T,and behind and pressing against clutch N.

P is a shaft to the left of axle X, as shown in Figs. 1 and 2, andjournaled at V V in the hangers VV and \V, and lying in the same linewith axle X. Gr is a large gear-wheel fast- F shaft situated belowgear-wheel G and at right 1 angles to shaft 1. One end of u is journaledin a cross-piece supported at each end by the hanger W and TV, and theother end isjoun naled in a hanger, b. Upon this shaft (1 is an endlessscrew, 1), which gears into wheel G. (t andf are idle-pulleysd for thehoistingbelt andf for the lowering-belt. c is the pulley operatin g theshaft a.

The mode in which the improvements in my hoisting-machine operate is asfollows: \Vhen it is desired to lower the platform the lowerin g-belt isbrought from the idle-pullewf onto pulley a. The latter, being made torevolve, turns shaft a, screw 1), gear-wheel G, and shaft P. Shaft P, bymeans of the engagement of parts N N of the clutch, turns axle X, and,with it, drum M immediatel y begins to unwind the cord D and to lowerthe platform.

Thus far the operation of this machine does not ditt'er from that ofmany other hoistingmachines, and if there were never any accidentalstoppage in the descent of the platform the clutch N N, spring l,revolving ratchet Y, and stationary pawl Z would be useless. Butfrequently the platform suddenly refuses to descend, and thehoisting-drum, unless im mediately stopped in its revolution, continuesto unwind the hoisting-cord and to snarl it in an almost inextricabletangle, besides often breaking said cord or some portion of the hoistingmachinery.

In the present machine, when the platform becomes fastened so that itrefuses to descend the weight of the platform no longer holds up thecord or the drum M; said drum, being relieved of the weight of theplatform, forces that end of the axle X which is on the right hand ofthe drum in Figs. 1 and 2 from the top to the bottom of the slottedjournal S. The

axle X, in falling, carries with it the ratchet-- wheel Y. As the axle Xand drum M and ratchet-wheel continue to revolve a tooth of theratchet-wheel engages with the stationary pawl and the revolution ofsaid ratchet and the axle X and drum M is at once stopped, and thus thecord 1) prevented from unwinding and all entanglement of it isprevented. Also, all strain upon or breakage of the axle X, or thegearingoperating it, as well asall slipping of the operating-belts uponpulley c, are prevented by the two portions N and N of the clutchdisengaging and pern'litting axle P to revolve. as freely as before. Assoon as the obstruction to the descent of the platform is removed theplatform again strains upon the cord, and as said platform is heavierthan the hoistingdrum the cord will lift up the drum, and with it liftthe axle X, to the top of journal S, thereby disengaging the tooth ofthe ratchet-wheel from the pawl Z and leaving said wheel free to turn.As spring F is continually forcing the points of clutch N into thecorresponding points of the revolving clutch N, and as N is now free torevolve, clutch N engages N, axle X and drum M once more revolve andunwind the rope, and the platform descends.

Claims.

What I claim as new is- 1. The combination of the ratchet-wheel or itsequivalent and a stationary pawl, substantially as and for the purposesspecified.

2. The combination of hoisting-axle, slotted journal, ratchet-wheel orits equivalent, and

\Vitnesses:

I 1. BLAKE, PHILIP M. SHUEY.

